Click the green flag. Then click space to advance. Have you ever seen a cool platformer that's really smooth and none choppy? Without any backdrops? That's probably a scrolling platformer. And it's really easy to make one. (This is the 2D version. Which was more easier.) If you wanted to make a scrolling platformer, wait for that tutorial or use this and try to recreate it into a scrolling platformer.
This tutorial was suggested by: @pinokioissocute .